The research proposed under this fellowship will examine the magnocellular pathway and it's role in reading. In the last few years, there have been a number of reports indicating a relationship between dyslexia and a visual processing deficit specific to the magnocellular pathway (M path). It is not clear how an M path dysfunction would cause reading difficulties, or even if the dysfunction contributes significantly to dyslexia.. Preliminary studies from this lab however, indicate there is an M path involvement in specific aspects of reading. Specifically, the M path seems to be involved with global orthographic processing. The research proposed under this NIH fellowship will be conducted to assess the involvement M path deficit has on reading performance and to show the specific reading mechanisms effected by M path dysfunction in adults and children diagnosed with dyslexia. The research project will be conducted in two parts. Part I: The first step to assess the M path involvement in reading will be to evaluate the vascular of currently available methodologies for inhibiting M path processing. The, second step will be to record and compare, in non-dyslexic individuals, neural activity associated with orthographic and phonologic processing tasks under M path inhibition and normal conditions. Part II: To test the hypothesis that an M path deficit is significantly contributing to reading problems in dyslexics, neural activity recorded under M path inhibition will be compared to neural activity recorded from dyslexic individuals performing the same tasks.